Today: Apple (AAPL) says it sold 4 million iPhone 4S units in first three days of availability, which is an incredible number. Plus: Stocks nose-dive, with Wells Fargo, Hewlett-Packard (HPQ) and BlackBerry maker taking big hits, and Alibaba CEO says company has money ready to buy Yahoo (YHOO).

iPhone 4S sales show increasing demand for Apple smartphones

After Apple announced the iPhone 4S earlier this month, a lot of media focus was on the lack of a brand-new iPhone 5.

Apparently, consumers were not as concerned.

Apple announced Monday that its newest smartphone topped sales of 4 million units in the first three days of release, more than double the initial three-day total for the iPhone 4. Apple’s senior vice president of world product marketing, Philip Schiller, said in Apple’s news release that the sales total was a record for any phone.

That’s a whopping number, as this breakdown shows:

— Even basing sales on 72 full hours — not entirely accurate considering sales did not start at midnight on Friday — 4 million phones would mean Apple sold more than 925 phones an hour, or more than 15 per second.

— As tech writer Dan Frommer points out at splatf.com, assuming that Apple received an average of $500 per device — remember, wireless carriers sell the devices at a loss in order to add to their subscriber base — then Apple’s revenues grew by more than $2 billion since Friday morning.

— When the original iPhone 4 launched in June 2010, it sold 1.7 million units in the first three days. Even given the different factors between the two launches — the iPhone 4 launched on a Thursday, not a Friday; the iPhone 4S debuted in two more countries and with one more major wireless carrier, Sprint; and supplies of the iPhone 4 were depleted not long after its launch, forcing some customers to wait — it is safe to say demand has continued to grow the for the Cupertino company’s smartphones.

The uptick in demand for one of Apple’s signature products could be attributed to many factors, RBC Capital Markets analyst Mike Abramsky told Bloomberg News.

“Higher-than-expected sales may have been the result of availability at Verizon and Sprint in addition to AT&T, broader international distribution, positive reviews, timing of the iPhone 3GS hardware upgrade availability and possible Steve Jobs tribute-related demand,” Abramsky, who had projected sales of 3 million units, said.

And Apple’s other new products, launched Wednesday, enjoyed banner debuts as well — the company announced that iOS 5, the company’s new operating system for mobile devices, reached 25 million people, and iCloud, cloud-based storage of electronic data for use on connected Apple products, received 20 million subscriptions.

Apple stock, which jumped in anticipation of the launch late last week, hit a new all-time high of $426.70 during Monday trading. However, stocks slid in the afternoon and Apple shares closed at a price of $419.99, a loss of $2.01, or 0.5 percent.

HP, Wells Fargo and Research in Motion stocks lead Wall Street fall

The slide that brought Apple shares down did a lot more damage to other companies, however, as all the major stock indexes lost about 2 percent or more on Monday.

The biggest dive was in the Dow Jones industrial average, which decreased 2.1 percent as investors fretted about Europe’s economy and poor earnings reports by some major companies. One of the biggest losers on the Dow was Palo Alto tech giant Hewlett-Packard, which fell 4.8 percent as stockholders showed concern that a flood in Thailand could delay manufacturing for the company.

However, HP couldn’t hold a candle to Wells Fargo. The San Francisco-based bank announced record profits in its third-quarter earnings report Monday, but reduced revenue sent the company’s shares nose-diving to a loss of 8.4 percent.

The Nasdaq suffered a 2 percent drop, with Research in Motion leading the way. The Canadian maker of BlackBerry mobile devices offered customers free apps and tech support on Monday to make up for large service outages suffered last week, but investors still punished the company by selling off stock — RIM shares ended the trading day down more than 6.5 percent.

The Standard & Poor’s 500, which had increased 11 percent from Oct. 3 through Friday, took the lightest tumble of the day but still fell 1.9 percent.

One of the winners on the day was Los Gatos video service Netflix (NFLX), which gained 1.1 percent as the rest of the Silicon Valley was watching their share prices plunge.

Alibaba CEO says company ready to put up cash for Yahoo

Alibaba CEO Jack Ma told a Silicon Valley audience earlier this month that he was interested in buying Yahoo and talking with Sunnyvale company executives about it, and now he says the financing is already in place.

“Do you know how much it will cost to acquire Yahoo? It needs $20 billion based on the company’s valuation today. … We have the most cash reserves among Internet companies, and we have already prepared $20 billion,” Ma said, according to iChinaStock News and Sohu.com.

Yahoo owns a 43 percent stake in Alibaba, one of China’s largest Internet companies. Even if Yahoo and Alibaba could agree on a price, they would still have to persuade U.S. regulators to allow a Chinese-owned company to buy a high-profile American company involved in communications.

Check in weekday afternoons for the 60-Second Business Break, a summary of news from Mercury News staff writers, the Associated Press, Bloomberg News and other wire services. Contact Jeremy C. Owens at 408-920-5876; follow him at Twitter.com/mercbizbreak.

A transit village with apartments, retailers, restaurants and a hotel is rising in Milpitas next to The Great Mall, close to light rail and the under-construction BART station. It’s one of several Silicon Valley projects sprouting up near transit.